E-mail address is noted as "bad" in e-mail address check; how do I resolve?

We have one member whose e-mail address rejects every time I send an e-mail to all club members. The message I get when I check her e-mail is: "No advertised SMTP servers are accepting e-mails." Is this something you can help me with?

Club website is: Cranberry High Noon Toastmasters
cranberryhighnoon.toastmastersclubs.org

We always need your club number.

Melissa is using a VERY SLOOOOOW mail service and it is timing out.

Thanks! I will let her know. Appreciate the very quick reply!